Non-volatile semiconductor memory device with contact plug electrically conductive in response to light

Abstract

Disclosed are a non-volatile semiconductor memory device capable of simplifying the complicated structure of a transistor, and a fabrication method for the same. The non-volatile semiconductor memory device includes a semiconductor substrate including a plurality of active regions, gate electrodes formed over the respective active regions of the semiconductor substrate, gate spacers formed over both sides of each of the gate electrodes, common source/drain regions formed on the surface of the semiconductor substrate at both sides of the gate electrode including the gate spacers, an interlayer dielectric formed over the whole surface of a resultant structure including the substrate, gate electrodes, gate spacers and common source/drain regions, and contact plugs penetrating the interlayer dielectric, and connecting the common source/drain regions to a data line, wherein the contact plugs are made from a material which becomes electrically conductive when in contact with light and becomes non-conductive when out of contact with light.

1. An apparatus comprising:
 a semiconductor substrate including a plurality of active regions; 
 gate electrodes formed over the respective active regions of the semiconductor substrate; 
 gate spacers formed over both sides of each of the gate electrodes; 
 common source/drain regions formed on the surface of the semiconductor substrate at both sides of the gate electrode including the gate spacers; 
 an interlayer dielectric formed over the whole surface of a resultant structure including the substrate, gate electrodes, gate spacers and common source/drain regions; and 
 contact plugs penetrating the interlayer dielectric, wherein the contact plugs are made of a material having an electrical conductivity in response to light. 
 
     
     
       2. The apparatus of  claim 1 , including a spacer oxide layer formed of an oxide over the gate electrode to surround the gate electrode. 
     
     
       3. The apparatus of  claim 1 , wherein the gate spacer comprises silicon nitride. 
     
     
       4. The apparatus of  claim 1 , wherein the contact plugs are made from arsenic sulfide. 
     
     
       5. The apparatus of  claim 1 , wherein the contact plug have the electrical conductivity by contact with light and a non-conductivity when out of contact with light. 
     
     
       6. The apparatus of  claim 1 , wherein the plurality of active regions are defined by a plurality of device isolation layers. 
     
     
       7. An apparatus comprising:
 a semiconductor substrate including a plurality of active regions; 
 gate electrodes formed over the respective active regions of the semiconductor substrate; 
 gate spacers formed over both sides of each of the gate electrodes; 
 common source/drain regions formed on the surface of the semiconductor substrate at both sides of the gate electrode including the gate spacers; 
 an interlayer dielectric formed over the whole surface of a resultant structure including the substrate, gate electrodes, gate spacers and common source/drain regions; and 
 contact plugs penetrating the interlayer dielectric, wherein the contact plugs are turned on by contact with light and turned off when out of contact with light, 
 wherein the contact plugs are made of a material having an electrical conductivity in response to light. 
 
     
     
       8. The apparatus of  claim 7 , including a spacer oxide layer formed of an oxide over the gate electrode to surround the gate electrode. 
     
     
       9. The apparatus of  claim 7 , wherein the gate spacer comprises silicon nitride. 
     
     
       10. The apparatus of  claim 7 , wherein the contact plugs are made from arsenic sulfide.